Merge pull request #111 from Automattic/undefined-this-in-trait

Don't report on undefined `$this` within Trait, similarly to class.

Author: david-binda

WordPressVIPMinimum/Sniffs/Variables/VariableAnalysisSniff.php

@@ -800,7 +800,7 @@ protected function checkForThisWithinClass(
             if ($tokens[$scopePtr]['code'] === T_CLOSURE) {
                 return false;
             }
-            if ($scopeCode === T_CLASS) {
+            if ($scopeCode === T_CLASS || $scopeCode === T_TRAIT) {
                 return true;
             }
         }

WordPressVIPMinimum/Tests/Variables/VariableAnalysisUnitTest.inc

@@ -3,4 +3,11 @@
 function foo() {
 	$a = 'Hello';
 	$c = compact( $a, $b );
+}
+
+trait bar {
+	function foo() {
+		$this->bar(); // Undefined $this in trait OK.
+	}
+	function bar() {}
 }